I am adding about 3000 rows to SQLite database and it takes about 8 seconds. How can I optimize this.
If you aren't already, wrap the entire operation in a transaction. Your code should look something like this:
db.beginTransaction();
try {
// insert your data here
db.setTransactionSuccessful();
} finally {
db.endTransaction();
}
Try executing PRAGMA synchronous = OFF before doing the updates.
Related
I have a large file of json after the parsing using JACKSON, I must store it into a database, it takes a several minutes so my questions
1-there's any way to speed up the storage ?
2- there's another database ?
3- Using Object database could help me ?,
I use SQLITE Database, I heared about RealM but I'm not sure to use it, help me guys
If you're storing directly the json inside sqlite you're probably doing something "wrong".
A database is useful when you need RELATIONSHIPs beetween objects, and so you have tables, indexes, keys and stuff like that.
Anyway, it's really strange that it takes minutes, but I suggest you to rethink your architecture, and maybe just write it on a file.
Changes in SQLite are ACID (atomic, consistent, isolated, durable). This means that every update, insert and delete operation is ACID. Unfortunately this requires some overhead in the database processing therefore you should wrap updates in the SQLite database in an transaction and commit this transaction after several operations. This can significantly improve performance.
The following code demonstrates that performance optimization.
db.beginTransaction();
try {
for (int i= 0; i< values.lenght; i++){
// TODO prepare ContentValues object values
db.insert(your_table, null, values);
// In case you do larger updates
yieldIfContededSafely()
}
db.setTransactionSuccessful();
} finally {
db.endTransaction();
}
REfs:http://www.vogella.com/tutorials/AndroidSQLite/article.html
Can we insert 1000 records in one go in Sqlite db in android. I know there is an approach of putting the loop and then calling the insert for 1000 times ?? Is there any other approach for this which is good in performance. And if this is the only approach, how much my performance would be impacted by this??
database.execSQL("PRAGMA synchronous=OFF");
Will enhance the speed database operations.
But it is risky in some conditions.
You should use transactions for such scenarios.
Pseudocode:
db.beginTransaction();
for (entry : listOfEntries) {
db.insert(entry);
}
db.setTransactionSuccessful();
db.endTransaction();
Check this post.
It has example of inserting values to database with and without transaction.
Also it has time measurment for this approaches(In this post difference is more than 100 times while inserting 100 records).
I have to execute a bunch of SQL rows in order to put some data into my tables. There's a lot of those rows (around 15 MB of raw SQL instructions), so I tried to use transactions in order to improve database performance. That's my code:
SQLiteDatabase db;
...
db.beginTransaction();
...
//in cycle:
db.execSQL(row);
...
db.endTransaction();
db.close();
But when I launch my app, I can see in logs that SQL scripts are executing, but there's no data in DB. And if I simply remove db.beginTransaction(); and db.endTransaction(); - everything works fine. Any ideas how I have to work with transactions?
db.beginTransaction();
try {
//in cycle:
db.execSQL(row);
db.setTransactionSuccessful();
}catch {
}finally {
db.endTransaction();
}
public void setTransactionSuccessful ()
Added in API level 1 Marks the current transaction as successful. Do
not do any more database work between calling this and calling
endTransaction. Do as little non-database work as possible in that
situation too. If any errors are encountered between this and
endTransaction the transaction will still be committed.
i am developing android app, here i am having an huge no of data approximately 10000 records with 10 fields in the server, i need to get this data and store it in the my local db, so for this i tried to implement by getting the data in the form of json parsing it and inserting in db one by one, it is taking less time to download the data but more time to insert to the db, after some time i get to know that i am inserting to the db one by one, so insertion operations looping based on the total no of records which had been got. i tried to look for the alternatives i could not get the way for this, so i request you to give me suggestions and snippets to me achieve this.
Thanking you
use transactions to wrap multiple inserts into one operation, that's a lot faster: Improve INSERT-per-second performance of SQLite?
List<Item> list = getDataFromJson();
SQLiteDatabase db = getDatabase();
db.beginTransaction();
try {
// doing all the inserts (into memory) here
for(Item item : list) {
db.insert(table, null, item.getContentValues());
}
// nothing was actually inserted yet
db.setTransactionSuccessful();
} finally {
// all inserts happen now (if transaction was set to successful)
db.endTransaction();
}
I made my own contentprovider where I put a lot of data in at once with multiple inserts.
The app will receive the data from an external source and at this moment I receive about 30 items (therefor 30 times an insert).
Now I noticed that this takes a lot of precious time (about 3 seconds, 100ms on each insert).
How can I improve the speed of the contentprovider? I already tried to bulkInsert them all together but them it will take up to 5 sec.
Thanks in advance.
wrap all that in insertBulk into transactions.
Example:
SQLiteDatabase sqlDB = mDB.getWritableDatabase();
sqlDB.beginTransaction();
try {
for (ContentValues cv : values) {
long newID = sqlDB.insertOrThrow(table, null, cv);
if (newID <= 0) {
throw new SQLException("Failed to insert row into " + uri);
}
}
sqlDB.setTransactionSuccessful();
getContext().getContentResolver().notifyChange(uri, null);
numInserted = values.length;
} finally {
sqlDB.endTransaction();
}
bulkInsert does not use transactions by default, since the default behavior just calls insert:
Override this to handle requests to insert a set of new rows, or the default implementation will iterate over the values and call insert(Uri, ContentValues) on each of them.
doing the inserts in a transaction greatly improves the speed, since only one write to the actuall database takes place:
db.beginTransaction();
try {
// do the inserts
db.setTransactionSuccessful()
} finally {
db.endTransaction();
}
I was once experimenting trying to improve the write speed of about ~2000 writes, and this was the only big improvement I found.
Doing db.setLockingEnabled(false) i think gave about 1% improvement, but then you must also make sure no other threads write to the db. Removing redundant indexes can also give a minor boost if the table is huge.